﻿using System;
using System.Runtime.InteropServices;

namespace UDPSocketProject
{
    public class Converter
    {
        public Converter()
        {
        }

        public static Byte[] StructToBytes(Object structure)
        {
            Int32 size = Marshal.SizeOf(structure);
            Console.WriteLine(size);
            IntPtr buffer = Marshal.AllocHGlobal(size);
            try
            {
                Marshal.StructureToPtr(structure, buffer, false);
                Byte[] bytes = new Byte[size];
                Marshal.Copy(buffer, bytes, 0, size);
                return bytes;
            }
            finally
            {
                Marshal.FreeHGlobal(buffer);
            }
        }

        public static Object BytesToStruct(Byte[] bytes, Type strcutType)
        {
            Int32 size = Marshal.SizeOf(strcutType);
            IntPtr buffer = Marshal.AllocHGlobal(size);
            try
            {
                Marshal.Copy(bytes, 0, buffer, size);
                return Marshal.PtrToStructure(buffer, strcutType);
            }
            finally
            {
                Marshal.FreeHGlobal(buffer);
            }
        }
        public static Object BytesToStructoffset(Byte[] bytes, Int32 start_len, Type strcutType)
        {
            Int32 size = Marshal.SizeOf(strcutType);
            IntPtr buffer = Marshal.AllocHGlobal(size);
            try
            {
                Marshal.Copy(bytes, start_len, buffer, size);
                return Marshal.PtrToStructure(buffer, strcutType);
            }
            finally
            {
                Marshal.FreeHGlobal(buffer);
            }
        }
        // 翻转字节顺序 (32-bit)
        public static UInt32 ReverseBytes(UInt32 value)
        {
            return (value & 0x000000FFU) << 24 | (value & 0x0000FF00U) << 8 |
                   (value & 0x00FF0000U) >> 8 | (value & 0xFF000000U) >> 24;
        }

        public static long ReverseBytes(long value)
        {
            return (value & 0x000000FFU) << 24 | (value & 0x0000FF00U) << 8 |
                   (value & 0x00FF0000U) >> 8 | (value & 0xFF000000U) >> 24;
        }

        public static Int16 BLEndianUshort(Int16 value)
        {
            return (Int16)(((value & 0x00ff) << 8) | ((value & 0xff00) >> 8));
        }
    }
}
